Ultrahigh‐Resolution Optical Fiber Thermometer Based on Microcavity Opto‐Mechanical Oscillation

High‐resolution temperature measurement is nerve‐wracking obstruction for precise characterization of many physical, chemical, and biological processes. To solve this problem, a novel microcavity–optomechanical–oscillation‐based thermometer is proposed. The microcavity serving as a link parametrically couples the mechanical resonator and optical resonator in the same structure and provides a natural and highly sensitive temperature transduction mechanism and ultrahigh‐resolution optical demodulation. The mathematical model of geometrical parameters, mechanics, and material properties for temperature response mechanism is established and verified experimentally. The proposed thermometer has a thermal sensitivity of 11 300 Hz °C−1 and an ultrahigh‐temperature resolution of 1 × 10−4 °C, to the best of one's knowledge, which is the highest temperature resolution with a silica cavity.